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Python add item to the tuple
I have some object.ID-s which I try to store in the user session as tuple. When I add first one it works but tuple looks like (u'2',) but when I try to add new one using mytuple = mytuple + new.id got error can only concatenate tuple (not "unicode") to tuple .
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How to get row from R data.frame
...- structure(list(A = c(5, 3.5, 3.25, 4.25, 1.5 ),
B = c(4.25, 4, 4, 4.5, 4.5 ),
C = c(4.5, 2.5, 4, 2.25, 3 )
),
.Names = c("A", "B", "C"),
class = "data.frame",
row.names = c...
dynamic_cast and static_cast in C++
...types are not related, you will get a compiler error. For example:
class B {};
class D : public B {};
class X {};
int main()
{
D* d = new D;
B* b = static_cast<B*>(d); // this works
X* x = static_cast<X*>(d); // ERROR - Won't compile
return 0;
}
dynamic_cast< Type* >(p...
Sorting object property by values
If I have a JavaScript object such as:
38 Answers
38
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JavaScript pattern for multiple constructors
...loading, including for methods or constructors.
If you want a function to behave differently depending on the number and types of parameters you pass to it, you'll have to sniff them manually. JavaScript will happily call a function with more or fewer than the declared number of arguments.
functio...
Find the max of two or more columns with pandas
I have a dataframe with columns A , B . I need to create a column C such that for every record / row:
2 Answers
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Circular (or cyclic) imports in Python
...retty thoroughly.
Imports are pretty straightforward really. Just remember the following:
'import' and 'from xxx import yyy' are executable statements. They execute
when the running program reaches that line.
If a module is not in sys.modules, then an import creates the new module
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Assign multiple columns using := in data.table, by group
What is the best way to assign to multiple columns using data.table ? For example:
2 Answers
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Javascript - sort array based on another array
Is it possible to sort and rearrange an array that looks like this:
21 Answers
21
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How can I count the occurrences of a list item?
...oop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the other answers.
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